[Cfp-interest 1433] Re: intmax_t

[Jim Thomas]

Let’s wait to see what WG14 does. Using long long for the (u)?fromfp(x)? functions would mean that wouldn’t work for any wider types.

- Jim Thomas

> On Oct 23, 2019, at 7:53 PM, Fred J. Tydeman <tydeman at tybor.com> wrote:
> 
> On Wed, 23 Oct 2019 19:15:24 -0700 Jim Thomas wrote:
>> 
>> A more detailed summary of the issue would be helpful. Is WG14 obsolescing intmax_t? It was particularly useful for the (u)?fromfp(x)? functions which meet the IEC60559 requirement for conversions between its floating-point formats and all integer formats.
>> 
> 
> Since intmax_t is part of function prototypes, it is hard coded in the ABI.
> So, if an implementation adds an extended integer type  (such as 128 bit)
> that is wider than long long, intmax_t will no longer be the widest integer
> type.  It is not clear to me what the committee will do with intmax_t, but
> we agree that it does not meet its design goal.  See N2425.
> 
> ---
> Fred J. Tydeman        Tydeman Consulting
> tydeman at tybor.com      Testing, numerics, programming
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